The objectives of the project are to study the early phases of normal and abnormal embryonic facial development concentrating on the neural crest and primary palate development. These studies are conducted on avian and mammalian embryos and the main areas of research are: (I) determination of the nature and origins of extracellular matrices related to crest cell migration; (II) experimental alteration of these matrix components and examination of the effects of these alterations on crest cell migration; (III) examination of the nature of primary palate development and spontaneous cleft lip formation in mice; (IV) studies of the interaction of genetic and environmental factors affecting the frequency of cleft lip formation in mice; and (V) development of whole (mouse) embryo culture system for teratological studies.